Saturn is the sixth planet from the sun. It is most famous for its beautiful giant rings.

Saturn is the second largest planet in the solar system after Jupiter. It is only slightly smaller than Jupiter in diameter, but is much smaller in mass. Saturn is made up of mostly hydrogen with some helium. The surface of Saturn is gaseous, but as you go deeper the hydrogen becomes liquid and then becomes metal. Saturn's center is a hard rocky core. Overall, Saturn is the least dense planet in the solar system. It is the only planet that is less dense than water, meaning it would actually float on a (huge) ocean of water. Saturn's surface can have huge storms and contains some of the fastest winds in the Solar System of up to 1800km/h.

The Rings of Saturn

Saturn's rings are made up of mostly ice particles with some dust and rocks as well. There are billions of these particles and they vary in size from specs of dust to rocks as big as a bus. The rings are located around Saturn's equator. They start at about 6000km above the surface and go to 120,000km with some gaps. The rings are around 20 meters thick and can be seen from Earth with a good telescope.

Saturn's major rings are named with letters. Source: NASA.

The Moon Titan

Saturn's largest moon is Titan. Titan is the second largest moon in the Solar System after Jupiter's moon, Ganymede. Titan is the only moon in the Solar System that has a dense atmosphere. Titan's atmosphere is made up of mostly nitrogen. It was discovered by Dutch astronomer Christian Huygens in 1655.

How does Saturn compare to Earth?

Saturn is very different from Earth. You couldn't stand on the surface of Saturn as its surface is hydrogen gas. Saturn's day of 10.7 hours is much shorter than Earth's while Saturn's year is over 29 Earth years. Saturn is also much, much bigger than Earth and Saturn has 60 moons vs. Earth's 1 moon. In addition, Saturn is unique from all the planets in the Solar system with its highly visible and gigantic rings.

Size comparison of gas giant planets. Source: NASA.

How do we know about Saturn?

Since Saturn can be seen with the naked eye, humans have known of the existence of Saturn since ancient times. Galileo was the first to notice that there was something around Saturn, but didn't recognize this as rings. Christian Huygens first noted that Saturn had rings.

The first space probe to visit Saturn and bring us close up pictures was Pioneer 11 in 1979. A few years later, Voyager 1 and Voyager 2 would bring us much better pictures and more information on the rings of Saturn. The first to orbit Saturn was the Cassini-Huygens spacecraft in 2004. This spacecraft sent a probe down to the surface of the moon Titan and brought us all kinds of information about Titan including that Titan has liquid present on its surface.

Drawing of the space probe Cassini passing by Titan. Source: NASA.

Fun Facts about the Planet Saturn

It was named after the Roman god of agriculture.

A year on Saturn is over 10,000 days. That would make for one long school year!

Many of Saturn's moons are named after the Titans. In mythology the Titans were the brothers and sisters of the god Saturn.

The large gap between Saturn's main rings is called the Cassini Division.